长江河口水下沙洲类型及典型水下沙洲的推移规律  

Categories of the Underwater Shoals and the Movement of the Typical Shoals in the Changjiang Estuary

作　　者：陈小华[1] 李九发[1] 万新宁[1] 应铭[1] 

机构地区：[1]华东师范大学河口海岸国家重点实验室,上海200062

出　　处：《海洋通报》2004年第1期1-7,共7页Marine Science Bulletin

基　　金：国家自然科学基金 [NO.50179012] ;上海市重点学科建设资助

摘　　要：对长江河口水下沙洲的类型及其演变规律进行了研究，把水下沙洲分为 4 种基本类型：节点型沙洲、弯道型沙洲、涨落潮流分异型沙洲、分汊口型沙洲。并研究了河口区若干典型沙洲在最近 20 a 的推移规律和冲淤状况，对沙洲冲淤量进行了计算，结果表明河口水下沙洲冲淤频繁， 1991 年后仅上、下新浏河沙 5 m 等深线内沙体每年冲淤量达 1.5×106 t，尤其是 1998 年大洪水导致上新浏河沙被冲失近 1/3 。The Changjiang estuary is characterized by regular bifurcations. The abundant water and sediment discharge of the estuary makes the shoals well-developed. Based on the cause of formation, in the estuary there are four basic types of shoals as follows: strait shoals, crook shoals, flood-ebb separating shoals, bifurcation shoals. The removing and erosion-accretion of the shoals is one of the main forms of the bedload movement in the Changjiang estuary. The bedload transportation due to the shoals takes place in tremendous quantities. Since 1991, the erosion-accumulation of Xinliuhesha shoal inside the -5 m line has amounted to 1.5×106 t/a. Especially in 1998, the floodwaters was an important factor of the erosion of the shoals, for example, the erosion loss of Shangxinliuhesha shoal summed to more than 1/3 of the whole shoal.

关 键 词：长江口 沙洲 底沙运动 冲淤 输沙量 + 

分 类 号：P737.23[天文地球—海洋地质] P737.121[天文地球—海洋科学]